In my continuing drive to upgrade my vintage amazons with all the near-period goodies I can find, I acquired a used but good 140 brake master cylinder, booster, standoff, actuating rod and clevis. This is destined to replace the externally boosted, 1800 dual circuit master cylinder and converter ring that I have on there now. I'll probably be taking the standoff to a welder for another custom firewall bracket tomorrow.

Anyway, as I said it was a used setup with quite a bit of surface crud and a bit of corrosion. Nothing serious - just dirty and needing new paint. The plastic check valve is in place and quite solid.

I would like to remove the check valve so I can treat the booster can metal for possible corrosion, but I could not seem to pry it out without using force that would likely break it.

I do not want to break it as I've no idea if and where I can find a replacement.
How does this thing come out? Does it come out without breaking? Where could I find a replacement if I break it? The mounting site looks tight and is probabaly free of corrosion. Maybe I should just skip scrubbing and painting and avoid breaking my check valve in the first place?

Since this is 140 technology (sourced from a 1973 I think) I though it best to ask in this particular forum