I would be careful with Acropolis.
Stanley Bet a UK bookmaker used to own StanleyBet.com (whose affiliate program was managed by Oxygen Marketing) and Acropolis Casino (whose affiliate marketing is managed by Electronik). They fall under the umbrella of Stanley Entertainment. A few months back Stanley Bet was sold by its parent company to Will Hill and all affiliates who had promoted StanleyBet were shafted. Oxygen couldnt do anything, but all the customers at StanleyBet were migrated to Will Hill which has its own affiliate system which pays a derisory CPA as opposed to a rev. share. So much for looking after affiliates.
I mention this because it is entirely likely that Electronik will be affected by a similar decision by the parent company Stanley Entertainment which will leave you stranded. There are so many playtech casinos to promote, I for one, would not spend a lot of money driving traffic to Acropolis given the way they treated their sportsbook affiliates.
There are some UK sportsbooks which have their own casino platforms like totesport which are entirely trustworthy and a core part of their strategy. If you are promoting to the UK market they would be my preferred choice and they pay commissions greater than $50.