info needed on fender bass tube amp

[SlipperySquid]

I have a friend whose after selling a fender music master tube amp (circa 1970's) but doesnt know how much it's worth as he was given the amp a few years ago?
Anyone an idea of how much they would go for etc? or what even the specs are for this amp (cant seem to find anything anywhere)
It's in good clean condition for age (with only a slight dent on metal where control knobs are).
Any help would be greatly appreciated!!!

[LukeFRC]

ive no idea but if you post photos you will get this hoard salivating