We will be travelling down by rail to our London game, on the Sunday before May Day.

I wondered if anyone could recommend a hotel around Ealing, that is en route to the ground, or, near Ealing centre?

From memory there's a couple on Ealing Broadway itself (around the green), I've never stayed in any though.
According to the missus, Alex Polizzi did one on her "Hotel Inspector" show.

Double tree by hilton near the green, travelodge in town all within reasonable walking distance.

Ealing town is OK if you want to stay local, the train station is mainline and tube so into London is easy enough and trains run late if you stay in town

Brentford has a Premier Inn and a decent Travelodge too.
The both call themselves "Kew" or "Kew Bridge", but they are in Brentford.
Buses that go to Ealing Broadway from there include the legendary 65 (which goes outside the Travelodge) or the E8.
Get yourself an Oystercard.

You won't go thirsty in Brentford either, nor really in nearby Kew.