Haha, yes i had it at 9 prov even. But it is too much, maybe just 1 bouncer. And 11 provisions or more.
Regarding the exact numbers.
For Wheel of Fortune one should consider the average value it creates, which is (1 + 10) / 2 = 5.5 (+ potential Crime synergy).
A single Casino Bouncer can pull 2 from the deck and is worth 4 points more than drawing a Casino Bouncer and playing it.
Regarding the 2 Bouncers you can pull with it we should consider the provisions to be 9+2 = 11.
A single Bouncer would be 4 * 3 - 1 = 11 points.
So Casino plays for 16.5 points on average, of which most points are carryover.
The best comparison to this card is Mushy Truffle, which has 6 carryover, rather than 11 and plays for roughly 8 points on deploy (with the SK Mermaid).
Truffle plays for 2.5 more points on deploy (0.5 if one actually misses all copies of the bonded units) and 5 points less of carryover, although Truffle also protects engines and triggers synergies (Alchemy + Assimilate) with its carryover.
Based on the above I would say that 12-13 provisions + spawning only a single Bouncer might be restrictive enough (given that value-wise the card is then on average 16.5 for 14, with thinning). One might argue that 11 provisions might be low enough, given that the large deviation in payoff from Wheel of Fortune is a significant downside.
All in all the card would be a mixture between Vernon Roche: Merciless and Mushy Truffle (if only a single Bouncer is spawned).
If you want to keep the provisions low you could also make it spawn a 1-strenght Casino Bouncer, given that it would still be 8 points of carryover on multiple bodies.
All the above aside I really like your idea. This definitely looks like a card that could exist and which has multiple precedents in the game (and it would make the less used thinning duo of SY actually worthwhile, similar to what Vernon Roche: Merciless and Cerys are doing).