a (very) cheap alternative, is to cover the damaged area with duct tape (electric tape). Make sure to do multiple layers.
In my ex-twinnie i cover the whole "spring" area of that part and lasted at least 2 years.
On the busso, i suppose it won't last that much, due to higher engine-bay temps.
Ofc, this is a temp solution only.
In my GTV sprortiva i have done the same, since i am rebuilding her all over (interior, exterior, mechanicals) and just wanted to avoid extra costs for now.
Definitely in the end, i' ll also get Autolussos' product, since it seem a good & dedicated (for our little bussos) product in fair price.