I have seen the plastic blade guides on some bigger/larger bandsaws, but they are adjustable in from side to side. The back bearing is still there, but not shown in this picture, so this only "fix" the side guides.
The problem with the blade guide was that the thread to the screws that locks the blade guide in place was out/broken. The screw had no grip (no threads at all) and the metal is too thin to drill a larger hole. I think the original blade guide mount/housing is made out of aluminium which is too weak in my humble opinion (atleast for the threading which has a stainless steel screw).
This small bandsaw I have is branded Meec (250 watt). It is very cheap and I really abuse it, so I'm counting on some parts to take a hit. But the threading falling out isnt one of them.
In the future I will have some adjustment to this saw made. For instanse I will build completly new blade guides, fix the dust collection, make a better table.
I know that John Heisz has a video on some of his improvements on this small bandsaw (and I belive this is the same type of saw, just branded different). Other bandsaws that has this desing, and that I belivie is the same saw (produced in the same factory but branded different by licensing) is Einhell, Titan and Harbor Freigh. It's only a guess from my part! :-)