Just as Tired Retired, I too own a Universal type 3 purchased many years ago.
As parts dry up, it's best to keep the tools away from these guns as much as possible.
Many owners of regular Carbines prefer to send a little solvent down the barrel so that some gets into the piston. Wipe out the barrel and then let it sit for a day or at least a few hours and then shoot it. Many tens of thousands of PSI will do wonders for stuck parts.
Let us know the results.
Phil