I have a Topeak Road Morph pump that, while touring, a bike mechanic in Europe sprayed some type of silicone lube into it. The problem was a squeak but it seemed to ruin the "O" rings. I have replacements from Topeaak but I would like to clean the pump. Or more accurately, de-contaminate it.
Any ideas of what to use?
Thanks!

Silicone is tough to get rid of since many solvents won't touch it. I'd suggest a thorough scrubbing using plenty of hot water and Dawn dish liquid before trying any aggressive solvents.
The spray might have been something other than silicone, since silicone usually doesn't harm rubber.

Here's a link to a product made for washing off silicone, but before you run out and buy it, I don't think that's your problem.

Silicone greases are SOP for neoprene O-rings, so I suspect that it isn't the silicone which ate toe O-rings, but a solvent. The solvent is probably long gone, so tie a string to a piece of rag, push it down the pump with a stick, and pull it back with the string. Once you've cleaned the bore, there won't be enough of anything to bother the new rings. However you might want to ask Topeak, what to use as an O-ring grease going forward.