"Pete C." wrote in message
...

A quick search show 2.750" ID and 3.125" OD honed hydraulic cylinder
tubing is a standard stock item. http://www.teamtubellc.com under
honed
tubing is one example.

While a hydraulic cylinder rebuilder was proudly showing me the large
honing machine he had designed, he mentioned that the requirement is
for smoothness, not straightness or roundness. The seals have
relatively a lot of compliance.

Here's another tubing supplier:
http://www.baileynet.com/
-jsw