I am thinking mid to late 60’s, with it's Formica case. Play is priced at 1np but the payout tube has the usual sleeve reducer inserted from the old 1d. I have seen similar wall machines which utilised GPO style relays but when comparing the wiring, this machine is a little poor in the neatness of the harness and the pvc colours and terminal blocks do look slightly modern. No name tag what so ever, although it looks a little home made, the glass is a proper screen print. I have never even plugged it in, but would love to find out its origins.
The percentage payout was certainly set in the operators favour!