Well in the end I bought a low pressure Gelert pump for £13.99 on ebay which I can leave to do most of the work as suggested. Just finishing the job off with my excellent Quicksilver manual pump. The new electric pump is pretty low power (Mrs T's hairdryer would do a better job!) but it does all the basic work without fuss. Plus I won't have to confess to Mrs T about any 'adaptions' to her hairdryer.
I think we will use the boat a couple more times this Summer and then go for something less involved. Mrs T fancies a Kayak.
So if anyone happens to be looking for a little-used Quicksilver SIB with a Suzuki 4hp four stroke engine plus some unused boat wheels in a few weeks time..