Just so everyone's clear, the OPX *I* am accustomed to hearing about is a line appearance at a street address other than the primary service address, which is multipled to a CO line, but almost never at the customer prem; it's commonly done at a cross-box (if local) or on the MDF with completely separately assigned pairs.

This is why an OPX won't help you for extending non-ILEC dialtone, which is what I gathered the OP actually wants to do.

What he probably wants is an "alarm circuit", which, if he can get it, is dry point to point copper, built from one site directly to the other, or sometimes through the frame, depending on the telco.

Lots of telcos detariffed those, because they let customers run point to point DSL privately, which telcos hate.