Rain Fly repair?

The round clear plastic portal in my Rain Fly came out last weekend.
The tent is a Rei Chrysalis UL 1. 44oz. I already bought a Fly Creek UL 1 to replace it... but I'd like to have the Chrysalis as a spare/loaner. Any suggestions? Get it repaired? Look for a replacement fly? I don't want to DIY.

If you bought it recently at REI they should take care of it, otherwise I would have someone repair it. Whenever I need any sewing done, I stop by my local dry cleaners. They do a pretty good job for a reasonable price. If you want someone more skilled in lightweight backpacking fabrics, you can try contacting various cottage gear makers and see if any of them is willing to do it. Many will (if they aren't busy).

It will also need to be seam sealed after the repair.

It shouldn't be too hard to fix, as long as the rest of the fly is in good shape. The first thing to do is to decide whether you want to replace it with a clear panel or fabric. If you want to replace it with a clear panel, you need to figure out what it was and where to find a replacement. Many of the clear panels are Vinyl. Vinyl starts out clear and flexible, but gets yellowed and brittle as it ages. Next, you need to know how thick it was. You might find some clear vinyl at an auto upholsterer and they could probably install it. If you don't want to fool with a clear panel, the best alternative would be a white fabric panel. Your local seamstress isn't likely to have the right material on hand, but you should be able to get some from on of the MYOG fabric suppliers. Removing the old stitching and sewing in a new fabric panel should be something that any one who does alterations would be capable of. You don't have to use white, but white fabric won't color the light coming through it.

Anyone ever tired these?

http://rainypass.com/

No, but I've heard only good things about them. They will also wash your down sleeping bag. Some consider them pricey, but IMHO the skilled laborer is worthy of his/her hire.

Well no need to repair. I took the tent by REI, hoping I could buy a replacement fly or maybe get a discounted repair. Manager said "Sorry we don't make that tent anymore... can I offer you a full refund?" Yes please!

Now that the situation has been resolved I will point out that historically those clear windows have been very problematic.
Several reasons including propensity to turn yellow and or opaque, cracking and having the stitching coming undone.
They do have a love at first sight appeal but I would reccomend to avoid them.
(nothing to do with REI , many manufacturers have tried them )