Well, this is one of those areas in life where you get what you pay for.
Cheap frames from the discount stores, Michael's, et al. are just that... cheap, generally poorly made and not anywhere close to archival.
Personally, if I have gone to the trouble to make the very best print I can something that is "frame worthy ", I am not going to compromise the final product with a discount store frame. That goes for prints on my own walls and doubly for prints that leave my house as gifts.
I try to keep to standard size frames, but when I need an odd size I almost always use metal frames where you can buy pairs of frame pieces in many sizes. Buy two pairs in the sizes you need. They go together easily and cleanly with a screwdriver.
I often use framedestination.com for these, but many art supply stores carry Nielsen Bainbridge frame sections that are a bit more expensive but can be had without needing to wait for delivery.
+1: I use Blick, but it depends on what sort of frames you want. For gallery shows I like a simple minimalist metal frame (usually black) and Blick sometimes has these on sale or with quantity discounts.
Frame Destination is good. They've been a Photrio sponsor, not sure if they currently are.
Good prices and a good range of products. https://www.framedestination.com
I purchase their custom mats - great quality and price. they are also provide good customer care and service, care for their employees (the pandemic!), and want to grow. (no, i'm not paid).
i use black aluminum 15x15 frames and affix the print with linen tape to the mat, no glass, no backing and hang 'em. I replace the prints in the mat frequently, and the mat itself when it becomes dirty. totally non-standard but nothing in the way of viewer and the print - easy to change out print without damage to print or mat.
i sell my prints for 20-30 bucks, un-matted or framed, and i give them away - they get seen.
Frame Destination is good. They've been a Photrio sponsor, not sure if they currently are.
Good prices and a good range of products. https://www.framedestination.com
I purchase their custom mats - great quality and price. they are also provide good customer care and service, care for their employees (the pandemic!), and want to grow. (no, i'm not paid).