To be honest, I have never been a fan of coin magic in restaurants and another reason why is its Australia. For me to get things like a coin bite or a expanded shell and such i need them all custom made, which would could me a bit.
You're needlessly overcomplicating things. You don't need gimmicks like a coin bite or an expanded shell in order to perform strong coin magic. In fact, a surprising amount of very good coin magic can be performed with the most rudimentary of coin sleights -- finger palm, thumb palm, shuttle pass, Bobo Switch; add a good retention vanish, the Tenkai Pinch, the Classic Palm, and (depending on what you want to do) Han Ping Chen and you have pretty much all you need for restaurant work.
Coin magic is PERFECT for restaurants, no matter what kind of coins are available to you. Coins are ubiquitous, especially in a restaurant setting; they are an ideal "borrowed object." If your routines involve ungimmicked coins, you don't even have to carry your own props, freeing your pocket space for other things.
Sure, you can rush out and buy gimmicks, but there is so much relatively easy to do strong coin magic out there that you really don't have to. A few things that come to mind from my performance repertoire are Tenkai Pennies, A Questionable Trick, Gadabout Coins, Scotch & Soda (I don't use gimmicked coins), Coins Across, Coins Through Table, Sheep & Thieves, a One-Coin Flurry...
Think about how strong it can be to just walk up to a table with nothing in your hands... borrow three 20-cent coins... make them fly invisibly from one hand to the other... then make them pass through the surface of the table one by one... then hand two of them back as you comment about how this one coin here is really the source of all the magic ("I bet you didn't even know you had one of these...")... go into a one-coin flurry ending with the complete vanish of the coin. They might not even ask for it back, which means you get a tip on top of it all.
Don't pass on coin magic. One of my single biggest regrets is that I didn't devote enough time to coin work in my formative years as a magician, and now I'm playing catch-up. But even so, I have still been able to pull together routines of strong coin magic without having to do any ridiculous knuckle-busting techniques.