Standard wagering requirement for similar deposit bonus is between 35-50x, but it usually wager on slots games is the one that counted 100% towards wagering requirement.
I just noticed that you have no slot games, so I think I have to revise my opinion about your 500x wagering requirement.
With the fact that the wagering requirement cant be done in all your in house games with 1% House Edge, I have to say that 500x is reasonable but of course lower will be better
Previously I thought that 500x can be done in slots game only ( I had not check your available games before), I was expressing my opinion in general.