jumper for Aragon 8008 b

Probably too late but I would get a XLR connector and solder the jumper onto that and plug in the connector to the amp. That way you don't have to worry too about using the incorrect wire size or damaging the amp connector accidentally with a burr on the wire etc ...

Are you talking about the jumper for shorting the balanced input? If so, just buy a piece of solid copper wire, strip the insulation, bend it with a pair of pliers, and VIOLA!