I've gat a Brother MPC-240C inkjet Printer, and Brother is not offering any drivers that work with MacOS Catalina. Are there any other sources of drivers that will allow me to scan or is my printer a semi-brick?

Your printer works in Catalina, both as

printer and scanner.

It is just the Brother Control Center software that doesn’t work, but you don’t need it anyway. Print normally. Scan using Preview.

That must be an old printer because the Brother site says it is only supported up to Mac OS 10.10 "Yosemite," which was replaced in Sept 2015.

Does the device still print on a very basic level? Often it is the other functions (copy; scan; fax) that require newer software. You should be able to scan using the Apple utility Image Capture, already installed on your computer. Certainly worth a try. See:

Scan images in Image Capture on Mac - Apple Support

If Image Capture cannot see the device for scanning, then I foresee a shopping trip n your future.

If it can scan but the printer side won't work at all, can look at third-party options, like gimp print. Search with a string like "gimp print brother mfc240." I'd leave off the "C" as that might be too narrow a search.