I've been looking for a nice one, for sometime now . High over low relief eagle doubled die reverse . http://koinpro.tripod.com/Articles/195950cRevVars.htm It's also coneca DDR-001 ( FS-801 ) http://varietyvista.com/11 Franklin Halves/DDR Detail Pages/1959PDDR001.htm
Here's a 66 that sold for, $463.88 cents in june of 2015 . http://www.pcgscoinfacts.com/Coin/AuctionDetail/145435/3300619/1
Here's the link to ebay . http://www.ebay.com/itm/1959-50C-Fr...e=STRK:MEBIDX:IT&_trksid=p2055119.m1438.l2649
Looking great! I have a few Franklin halves, but none that look that nice. Or any with errors for that matter.
Not a proof, but it was struck with the reverse die used on proof issues. Nice find, its on my search list too.