I am wanting to purchase a viewfinder for my GH1 but am having difficulty choosing one as every model says is for 5D, 7D, T2i. I can't find one (reasonably priced) that states support of GH1.
I was looking at this LCDviewfinder clone's here LINK.
I have both the 7D and GH1, and my Hoodman fits both. But realistically, you really don't need a LCD loupe for the GH1, the EVF is one of the big reasons why I got a GH1.
If you got lights behind you and you dont want to shove your eye into the little builtin one then its good to have. Luckily i havent encountered that issue.
I use a cheap eBay chinese version of the HoodEye. It's just a rubber shade cup for the EVF. I just superglued it on after unscrewing the plastic front of the EVF, then screwed the assembly back on once it dried. Works pretty well and keeps out stray direct sunlight on bright days. I cut it down a bit to fit my face but cut a bit too much off the "nose side." Only cost about $5 though.