line lock orientation

ok, what about this ?

Swagelok®3/16 Tube OD x 1/8 NPT Male Pipe STRAIGHT CONNECTOR 316 Stainless Steel | eBay

steel -check
high pressure- check (10,300 PSI)
NPT so no sealant required- check

looks like a winner?

You betcha, but I would still use Teflon tape on it to make sure I didn't end up with wet spots.