Unfortunately I don't believe so. For now, after MUCH soul searching, I went ahead and ordered without cuts. Troy got back to me and said we could cut the bolts later. If it were possible to get a removable plate as you describe, I would have been all over that!!! With all the guys out there that have both Mini and Micro guns, you'd think that it would be popular? The idea of having separate top covers doesn't thrill me. Just more expensive extra parts to keep track of.
So...I used to have a RR Micro UZI and sold it some time ago. I do miss having the complete 'family' but I rarely shot the Micro. I wanted to remain authentic so I ran it primarily in closed bolt since IMI never made a factory open bolt Micro.
In either case (open or closed bolt), I found my Micro to be very inaccurate in full auto. In semi, it was very accurate. I don't think I'm that bad of a shot either. I have always suspected that the receiver may have been flexing or something. I never did figure it out.
All that said, I would think a heavy bolt in a thinner receiver as the Micro has would be even worse and it isn't a true factory variation either if anyone cares about that as factory Micro's were never open bolt much less a heavy version.
IMHO, if you have a Micro, run it in all it's glory with the full 1700+ RPM.
I know the BarrelXchange heavy bolts are not true 'factory IMI heavy mini bolts' either. I think we all know IMI did make Mini heavy bolts but I can't recall seeing pictures of how they did them. I doubt they were modular which makes the BarrelXchange ones better IMHO. I do know that all the bolts I have gotten from BarrelXchange have been top notch with no issues.