solotk, good luck with the project. On the basis it will be a taxiable replica, why bother with engine authenticity?
I know of one guy who built an extremeley accurate Hurricane replica and powered it with a car engine (a Jag V12). This gave the right number of cylinders, the right sound and enough grunt to fast taxi the aeroplane.
The Jag V12 would fit in the slim nacelles of the Whirlwind better than anything I can think of cos the Peregrines were quite a lot smaller than a Merlin. The Jag engines (£500 each from the local scrapyard) would be a lot cheaper than Merlins (£15-£20k) too
