Need a final bit of help if you have an oil gun for sale

I've been searching for a couple of months and cant find an oil gun that will be long enough to reach the landroll of a ransomes mower.  Ive seen some I believe may work but are £30 plus. I'm in the final stage of re assembling my mower and would like to flush oil through. I have saved searches on the Wanner gun and have find nothing that is the correct serial number I've seen recommended here.