Threaded inserts for 3D printing?

Is there anywhere convenient to get threaded inserts for 3D printing or do I have to go to Amazon?

Thanks.

Gonna be Amazon, I’ve yet to find anything local

I’ve found a limited selection of threaded inserts at Lowes but it is all small quantities of larger imperial sizes (3/32 and 1/4-20 and larger) and generally very overpriced. Haven’t found any metric ones at Lowes. Amazon’s going to be your easiest bet for this, or McMaster Carr if you need something specific and high quality.