112 RP (copy ?) needs identification

Hi,
i've got the amp described at http://eric.fouillaret.free.fr/ampli.htm
since 15 years now. I never used it and when i began researches recently in order to buy it, i found that it (really)looks like a 112 RP.
The front panel is quite similar and the rear panel too (except what could be a second extension speaker jack on the right side).
The tubes are EL34
I don't think it can be a real music man amp (cos there is no logo nor inscription) and it looks like a home made copy.
Could someone give me an expert advice.
Thanks in advance
Eric

Looks legit to me, although I haven't seen too many rp's in person. Just looks like someone re-housed it in another cab and (for some reason) removed the front & rear faceplates.
Dan

Thanks Dan for your advice.
Yes it can be (or can has been) legit, there is just that detail of the second (third in fact) jack input on the rear panel right side that i haven't seen anywhere else up to now.
Eric

You know, I totally missed the "1 autre sortie jack ?". Must be a mod of some kind, although I wouldn't know what. The amp already has an "effects loop" of sorts with the in/out jacks on the front panel. Could be a third speaker out jack someone wired up for some reason. Have you pulled the chassis and looked inside? With some pictures of that area inside the amp, some folks on this forum might be able to tell what's going on in there.
Dan

Yes , i can take pictures of the inside, but before i'm gonna try to plug another speaker in this extra jack input because i'm not quite sure that i have tried it yet ..
Eric