It's not a huge museum, but it's well worth a visit when you're nearby. Go on a nice day, since the locomotives and rolling stock are not under cover. Nice O-gauge layout and other displays are inside the building. The layout was covered in a TM video a few years ago.
The only noteworthy train shop in the area that I'm aware of is Jerry's Trains in Granger. IIRC, the best source of info regarding days and hours is their Facebook page. Owner Jerry Macri is a skilled and prolific modeler, and has one of the largest privately-owned HO layouts in the country in his home. Although the shop is primarily HO (with a lot of used stuff), there is also a decent selection of older O gauge and lots of books. Be sure to eat at Macri's restaurant while you're there.
There's also Rupel Toy Trains in Dunlap; their Facebook page makes it appear that they're still in business. Not a lot of trains - I think it's now more of a gaming store. Last time I was there, he also sold guns and cigars; if he got a liquor license, it would be one-stop shopping.
