The C506 with 8mm aperture might be a good fit for you. Plenty of room especially if speed isnt hugely important.
Working on a 6mm aperture mirror set for C506 right now but might be a bit small
I have these basically in stock right now.
These were originally custom designed for Rick Hale (slicklasers). I believe he uses them in some of his very high power projectors and can tell you exactly what you can expect in terms of performance.
We typically sell just the scanners for $350, and then Alex Hay at Laser Fantasy provides and tunes amps and supplies cables.
Feel free to send me an email at the address below and we can get into a private discussion about what you need and budgetary restraints, and we will see what we can do for you!
Sincerely,
Ryan Smith
ScannerMAX Mechanical Engineer
ryan {at} scannermax.com