Here's the link. Thought I'd share.
A bit small volume but it will hold 250 psi. There is a port on each end so putting two of them together with a nipple should be no problem.
MFG: Bimba #D11846-A-11 PORTS: 1/4" NPT
Vol: 70cu/in LENGTH: 10"
Air reservoir with 304 Stainless steel tube and aluminum heads. 250 PSI max pressure. Port in both ends
L: 13-7/8"O/A DIA: 2-5/8" WT: 1.66