Make your own using stock rims!
I've had it this way for years, ZERO PROBLEMS
1. Go to the local auto store and buy 4 valve stems (preferrably the short ones)
2. take your front stock rims, flip them around and drill a hole (size of hole will be on the valve stem container) in your rim on the OPPOSITE side of the stock valve stem. I try to line is up on the opposite side so it helps with balancing. Smooth any burrs (important) from the hole.
3. Take the valve stock valve stem and insert it in to the rim, so the long part with the schrader valve is INSIDE the rim. Basically install the valve stem backwards and pull it in to the rim to seat it.
4. With your new hole, install a new valve stem
5. put your tire back on (sometimes challenging) and fill up your tire with air, look for leaks.
6. Install on banshee (the part that used to face outwards now faces inside.
There, you just made offset rims and it cost you $5.00 in valve stems from the auto parts store.
I currently have two banshee's with this setup and 3 other friends I ride with have this exact setup.