Yes I saw it on eBay too.
Serious point if I may, single seaters are interesting beasts to get to know. I don't know how serious you were about your first flight being a 150nm ferry, but I noticed on the eBay ad that it was out of permit anyway.
If I were you I'd camp out at Fenland for a few days whilst the permit revalidation is done, then get the PFA check pilot to brief you thoroughly, make notes, get permission to do some fast taxis and low hops, make more notes, go and do some 20-30 minute local hops, make more notes. Then sleep on it and think about the long trip home.
And if you have a choice of check pilot, John Brownlow isn't far from there, and is both a TP and an instructor - you could do worse than look him up and ask him if he'd do it, you'll get far more sense from him than somebody at "the other end" of the experience spectrum.
You'd probably have done all that anyway, but I wouldn't have forgiven myself for not reminding you of the commonsense of converting to obscure single seaters.
G