Nice coin but the date is wrong. George II was long dead by then. Very interesting however, I'd look at the books for options. Several come to mind, including a mint error on the reverse.
1970 COMPASS-
WHITES SILVER EAGLE-
WHITES DFX, 4X6DD COIL, 6X8DD COIL, 950 COIL, 10X12SEF COIL-
GARRETT PRO POINTER AT, GARRETT AT PRO , MINELAB EXPLORER SE with 8.5x12.5 Cors coil
ALRIGHT......I think you'll find it's actually an 1787. Either the M.48-g.5......or M.53-FF. Reverse is tough. Would have to see it in the metal. I believe it is the M.48 OBVERSE for sure. That would then match up with the g.5 reverse. EXTREMELY RARE. R-6 or 7 Would need more input from other members. It's NOT a 1788. None of the varieties I see pictured in Breens would allow it to be a 1788. C-4 would like to see this one I'm sure. Nice find......Hogge