Rc 60 +/- is probably quite close. One lathe at a vo-tech I taught at had a spindle adapter for a collet closer that was not concentric. Off by 2 or 3 thou, but that was too much IMHO. This was before hard turning became a thing so I just used a standard cemented carbide boring bar for the repair. It worked and I had collets running much closer to zero TIR. BTW, it was also around 60 Rc.

So if push comes to shove and you cannot find a wheel at least there is a plan B.

Here's a link to a site offering good info on hard turning/boring. http://www.superprecision.com/hardtu...echniques.html