Amp seem the Scandinavian model. Appears to be a 1987 50 watt model with 4 inputs. Headshell is not original to the amp as only 100 watt JMP's had vent on top. 79 is first year for JMP serial on front so good possibility its a 79. Canada & Scandinavia models have no 16 ohm speaker tap so limited there. Also these two export models have internal mounted fuse boards. Daly filter cans seem original. Likely time for new ones if going to be gigging, replace the bias caps as well.