I have three places I can generally find something like this; Amazon, eBay and AliExpress.
First I'd like to clarify about your lens. The ones I'm familiar with have a little glass circle within each of the camera lenses, surrounded by a bezel. As you've found, replacement is simple; just pry out the old glass, clean the old glue and stick a new piece of glass in.
Yours seems to be a little different. From what I can see, it looks like it's one molded piece that covers all of the cameras and flash rather than individual circles of glass. Here's a picture from an AliExpress listing for your phone that seems to show what I'm talking about.
[image|3663782]
If that's right then the associated listing should get you what you're looking for; apparently it comes in black or blue to match the back of your phone.
[link|https://www.aliexpress.us/item/3256805740359393.html|Rear Back Camera Glass Lens For Motorola Edge 40 Pro Edge+Plus 2023 Moto X40 5G Replacement+Adhesive Sticker XT2301-5 XT2301-1 - AliExpress 509]
Here's pretty much the same listing on eBay.
[link|https://www.ebay.com/itm/267250163439|2pcs New Rear Back Camera Glass Lens For Motorola Moto X40 edge 40 Pro Edge+ 5G - eBay]