Installing g++-4.9 on Debian 10 (buster)

Question

I have a legacy code that needs g++-4.9 to build. I am on Debian 10 (Buster). Is there a way to install g++-4.9 on Debian 10?

My default gcc and g++ version on the system is 8.3 But I also already have gcc-4.9 installed in my system. But I need to install g++-4.9.

I tried searching for solutions and found some posts telling me to add jessie or xenial to apt list, but other posts cautioned against doing so!

I found another post pointing to installing .deb files, but I could not find the .deb files following the links in those posts.

Any help is really appreciated! Thanks!