Have a slight leak on a manablock stem, has anyone replaced one and know the part number, appears to be an older style than today's units.
Is this the same part??
Viega 50602 PureFlow Zero Lead Manabloc Valve Stem Replacement Kit Red and... (https://www.amazon.com/Viega-50602-PureFlow-Manabloc-Replacement/dp/B008J31Z7W/ref=mp_s_a_1_3?dchild=1&keywords=manabloc+water+manifold+parts&qid=1598720733&sprefix=manablock&sr=8-3)
Is it possible to just replace the o-rings?
I have a box of them. I think the stem just pulls out, good idea
I have never replaced one, but this video shows how to remove one using the tool that is shown in the link you posted.
Manibloc valve stem replacement (https://www.youtube.com/watch?v=BILQLCCFVO0)