I bought $600 worth of the heavy duty ones last year -the link is posted below . I got 3 types of finish on themmostly stainless brushed I went for quantity discounts. These are Crystal porcelain potters who do some of the same shows as me with cystal work-very nice pots as well as some highly tecnical insect drawings on clay that look like photos.
I just arranged to pick them up at a show in another state as I know them.
They make mold collars as well but my body is a different shrinkage rate.
You can also buy the heavy duty ones at Aftosa as well
Heres the link as Min posted above a few years ago
Modern Heavy Duty Flat Head Stainless Steel
all these tops have the same guts as the palstic pumps the only improved part is the outer metal skin which is looks only
This link is also another accountancie who sells ceramic items but has pumps but are not as nice-he has some nice frogs for flowers if you need them.
His name is Chuck and he like the other link above both have china connections and do thier own importing
Both are nice people as I have met them all.
PS I have no financial tyes to either
PPs get on aftosa's e-mail list as they always have e-sales via e-mail-then you can buy many things at a discount
like right now its 20% on all surface protection items like rubber bottoms stick ons etc