If its just the valve seals, think it would be okay to ride it out for the summer and do the engine work when the snow starts falling?
Absolutely! That is exactly what I would do! In the mean time you can research what and how to take on this task. When I bought my KLR it had damaged cam bearings. So when I eventually got around to taking care of the engine I did so with the resale value of the bike in mind.
I put in a new stock (100.0 mm) bore Piston with Rings because the original bore was, well, original. That and because I couldn't find any source for just new stock piston rings. Thought about a 685 Kit, but just didn't see the value when compared to what the entire bike is worth. It almost certainly will wake the bike up a bit, and if the original bore was worn in any significant way . . . then, OK! But otherwise? No.
Sent the Cylinder Head out to have Cam Bearing Inserts installed by Mike (or Jenny) at Engine Dynamics, 2040 Petaluma Blvd., Petaluma, CA 94952 707-763-7519
Bought a motorcycle valve spring compressor on eBay for $15 and installed the Valve Guide Seals. It's a pretty simple procedure with the Cylinder Head off the bike.
As long as things were torn apart . . . . replacing the Doohicky was a given.
Also did a bunch of other miscellaneous stuff to the engine, as well as the rest of the bike, that I read about here on this forum and elsewhere.
The end result is an essentially new 2007 KLR650 for a total investment of slightly under $3,500.
FWIW I'm NOT having any noticeable/measurable oil consumption issues over the past few thousand miles. I've kept a really sharp eye on it as I don't want to repeat the error of the previous owner. This is with a 14 Tooth Counter Sprocket. So the engine is really spinning within about 1,000 RPM of red line at the 70-75 MPH that the freeways move here in the L.A. area. (Not in rush hour of course. LOL)