I recently got this at very close to melt. The seller thought it was a mishandled proof, but was obvious from the photo that it was the prooflike uncirculated version of that coin. The main difference is that the devices are not frosted and slightly reduced detail of strike. I will post pictures of the proof later for comparison. The uncirculated PL coins were struck to a total of 200 pieces, and all evidently put into a bag and have seen about three specimens, all with bag marks consistent with that (as with this piece).
Interesting. Haven't seen the 1977 set from Franklin Mint, but the singles up through dollar denomination are listed in Matte (M) but not listed in Krause as a set either - I think you may have been referring to the "non-FM" set? I tend to like the mattes better really though. An interesting side note: the only matte sets I have seen personally are those 1975 FM matte sets of Panama put together by the bank there. Also, I have a 1975FM Barbados complete matte set but in a Capitol holder for a very long time - I don't believe the Central Bank in Barbados did that one.
Nice pick-up. Did these not come in all the Franklin Mint sets? I can't remember what they did in each year but I thought there were uncirculated and proof sets in all years at least (matte in some) and they all head the five dollar coins. I only collect the circulating denominations so maybe I'm getting mixed up with the Cook Islands sets.
The mint sets started in 1978 strangely and supposedly about 200 struck and sent off in a bag. They all have bag marks (that I have seen). So 1977 were in proof sets only but not in the specimen sets.
Oh you're right - no mintage is given for the 1977 uncirculated sets. That would explain why I haven't completed that year!
Actually, I have no idea where I recorded the mintage but I have 14,000 as the proof mintage for 1977.