This is a nice example of a rare type. Probably a bit over-priced at $499.00 though.
The guy selling it also seems to be mainly a US coin person as he describes this coin as "Mint State" and he uses a rarity scale known Sheldon- Breen Rarity Scale and calls this coin an R6 with 13- 30 examples. Not surprisingly, he was also off a little with the RIC number and called this one Rome 216.
Crispus
A.D. 320
19mm 2.8gm
CRISPVS NOB CAES; laureate and cuirassed bust left with with spear pointing forward, shield on left arm.
VOT/XV FEL/XX in laurel wreath in three lines; mintmark on third and last line of legend- RP
RIC VII Rome 222