Hi Steve,
For the amount you'd pay someone to do it I'd just learn to solder. A cheap-ish soldering iron will probably do what you need and you'd only need to buy the iron (usually with the stand and cleaning sponge), some solder and something to practise with. I'd suggest getting some wire of approximately the same thickness as you're planning to solder and practise tinning the wire until you're good at it. Just tin the wire (youtube will show you how), cut it off and go again.
Once you've got that soldering the connectors on will be easy.
Alternatively, if there's not a member locally and you fancy a trip to Cambridge, look up the Cambridge hackspace and pop in there. I'm sure many people will be willing to help you get started.
Good luck :)
Stuart