Prelude: Replacing headlight wiring

1993 Prelude Si VTEC (Jap import)

I have 3-prong headlight bulbs and the plastic female plug on both of
them has partially melted over time which leaves the headlights with an
intermittent connection.

My local dealer said my options were to get a new wiring harness
(approx EUR 200 plus fitting) or to pick one up from a salvage yard. I
found only one matching Prelude but it had a 2-prong plug.

Anyone know of a good (& preferably cheap) way of fixing this? I
imagine there must be a generic plug I could use and join them to my
existing wires. I've tried tightening the spade connectors but this
only has a temporary fix.