Any advice on sending framed pictures (with glass) safely?

[mrssmiling]

I have a few small framed pictures (simple wood frames with glass over the print), which have retro appeal, and would probably sell for around £15-20 each, looking at current sold prices.
I wondered if I could send them via Royal Mail, securely packaged with lots of bubble wrap in a card sleeve/box - can't work out if I can get insured with glass? Any advice appreciated, thanks.

You won't get insurance.
I can pack well enough to do this.
Basically, pack the item entirely (all edges & sides) with bubble wrap/balled paper etc. inside a narrow cardboard box (make a box if you have to). If you shake lightly, nothing should move inside your box.

Now, place that entire box inside another box, also padded out with peanuts or other padding material. The inside cardboard box must not touch any of the sides of the outer cardboard box. Those inflated sausage shaped things are great for keeping weight down. Pad & Fill the box well. Tape it up... If you shake lightly, nothing should move even a mm inside.

You should be able to throw that whole package down the stairs and glass frames inside will not break.

If it's too huge to post with any courier... that's a different problem.