If it's really a pinhole leak then clean everything up very well with some brake fluid

/ solvent.

Then give it a go with some liquid metal type stuff, and if it holds you've saved a bit of effort swapping it out.

.

.

If you want to do it properly then of course a proper replacement would be on the cards.

.

.

but I'd probably go with the first route, if it doesn't work you've only lost out on a few pennies worth of gunk.
