[Vwdiesel] Piston Recommendations?

[Will Taygan]

My machine shop is having difficulty sourcing 1.0mm (2nd oversize)
pistons for the '82 Westy (originally CS, putting a ME mechanical into
it.)

AutohausAZ has Kolbenschmidt NA 068107091D pistons for $90.37 each. I
assume these are German.

Busdepot has the same ones for $115, and turbodiesel? 068107091BD for
$78 (maybe without rings? maybe Brazilian? maybe just a good deal?) and
German KS turbodiesel? 068107091C w/rings for $85.

EKTA only lists the BD as a TD piston, and doesn't list the C.

Really I'm looking for the steel reinforcing rings, I assume the NA
pistons don't have them and the TD pistons do?  I got that impression
from the Parts Place catalog, but I don't always trust their claims ;)

Just thinking of using stronger parts in the big van.

..and does it make sense that the German TD pistons are cheaper??

Thanks,

Will in Alaska.