There are better books, but I believe the now-free version of the old version of ERIC (Roman coin catalog) is here. http://www.dirtyoldbooks.com/eric.html A review of the subsequent volume, ERIC II is here: https://www.forumancientcoins.com/dougsmith/ericii.html I almost never use ERIC, but it's pretty darn nice for free (ERIC I, the 2005 version, is). Lots of pictures, too. I haven't downloaded it in some years, but to the best of my recollection, the dirtyoldbooks (Suarez ran dirtyoldcoins, I think) is the link. Run any downloaded file from the internet through a virus checker.
I have heard that Zurqieh puts an artificial patina on the coins, something that I wouldn't be able to tell myself not really being an expert, but that's kept me from ordering from him. On a completely separate note, as an example of second-century denarii, these were all purchased from between 50-75 dollars, with only one breaking the $100 barrier, which is the Lucius Verus. ANTONINVS AVG PIVS PP COS III, laureate bust right / DES IIII, Virtus standing left, holding spear and parazonium. Laureate bust of Hadrian right "HADRIANVS AVG COS III PP" Roma seated left, holding a branch and spear. "ROMA FELIX" TRAJAN AR silver denarius. Rome, 103-111 AD. IMP TRAIANO AVG GER DAC P M TR P, laureate head of Trajan right, drapery on left shoulder. Reverse - COS V P P S P Q R OPTIMO PRINC, Victory advancing left on pile of shields, wreath upward in right hand, palm in left. 2.92g, 17mm Laureate head of Lucius Verus right "L VERVS AVG ARM PARTH MAX" Pax standing left, holding a branch and cornucopiae "TR P VI IMP IIII COS II", "PAX" in exergue. So, I would say with your current budget, you could build a semi-complete set of second-century denarii. Nerva, Aelius, Commodus, and Marcus Aurelius are the only ones I'm missing, more due to scarcity than anything. They have a nice even size and work well as a set, and if you want to be picky you can choose matching or similar reverse types, or separate them thematically. They're not huge coins, maybe between the size of a US dime and a cent if you're going for denarii, but then again if you like copper or bronze, sestertii are a great choice as well. I've wanted one for a long time but haven't been able to find one that I really gravitated to and could afford. Sestertii are more the size of a half dollar.
Yes, there are quite a few from Zurqieh with the orange patina. However, I usually avoid those and go for the actual uncleaneds, or as about as close to uncleaned as one gets nowadays: And he's good for Parthian/Sassanian stuff Example: Parthian: (not uncleaned) Uncleaned: Uncleaned Parthian silver drachm Uncleaned nummus of Maximianus. One of the few orangies I bought: It's a really nice example of anAurelian/Vabalathus Tetradrachm, and was about half the cost of similar quality from other dealers: I'd probably recommend holding off on Zurqieh till one is a more established collector. His barebones description and the occasional fishy coin make it probably not great for the beginner. And his pictures aren't the greatest (the lighting). He must have gotten an enormous hoard of Heraclius Hexagrams. They were less worn than is the norm, but were harshly cleaned. I mined out the best of those remaining. I'm guessing the ones with the blue background are from Aegean? Aegean is another good dealer.
I haven't bought all that much from him,but I've received fantastic service, and I've been very happy with my purchases.
The dealers I recommend and personally bought from are: Aegean Numismatics Ken Dorney Incitatus Coins Civitas Galleries Lodge Antiquities Germania Inferior Numismatics Musa Numismatic Art Minotaur Coins Davissons I also purchase my coins from fellow collectors on Ancient Coins Facebook groups.