I have got a few spare parts that you could get for the price of postage.
* A working controller for an IBM M2. The capacitors work now, but I can not guess how long they will last. I may also have a few spare key caps.
* Some ~80 black ALPS sliders, springs and tactile leaves. I got them from a Dell AT101W that was in nice condition when I got it.
As I have replaced them in my keyboard with dampened sliders and clicky leaves, I do no longer need those that were in there from the beginning. You may have to clean and lube them.
I also have some switch casings, with bottoms from white or cream switches. If you want them then you would have to pay me for desoldering them, as that would be a bit of work.
The items are free, but I would like you to pay me for what it costs to post them to you. One of the above costs 3 Euro within the EU. I take PayPal.