Your original Compaq vendor can get the parts (and should know what you are asking about)
It is a genuine p.i.a. as an issue.
True story that may not help:
There was a large local chain that went out of business, and I went to the bankruptcy sale. They way it worked was that you negotiated with the bankruptcy representative as to the final sale price of an item.
So among other things, I pick up a case of 100 item count, Compaq rail kits. The bankruptcy representative wants $12.30 per item in the 100 count box. I offer $1 for the whole deal, we agree on US $2 for the 100 count box. Behind me in line is a fellow IT guy, in charge of a large US Government site. "Bill, you got robbed. Compaq would supply me with rail kits for free."
22 days later the same guy calls me "Hey Bill, you still have any of those Compaq rail kits?"
"Sure, US $12.30 each" I ended up giving 30 kits to him for free, but it was sure nice to hear his attempts to argue the point.