If one keeps the Marders running (They are whored down a little bit...
) they are for sure a good supplement to the armored formations.
The "keep them running" is actually something one should worry about. They will need some rebuilding if you want to have fun with them.
What kind of ATGM does Chile has in service?
IMHO it shouldn't be hard to adopt any ATGM one wants onto the mount of the MILAN on the Marder.
I would also expect the Netherlands to be a possible source of Gepards.
They are throwing away their stuff even faster than we do and also much newer toys.
Are the dutch Gepards upgraded?
What kind of SPH does Chile operates?
There are plenty of M109s available in Europe for sale.
And some of them have been modernised just recently and also feature things like a longer barrel. For example Switzerland wants to get rid of some of theirs as well as we do.
The Netherlands are even offering nearly new PzH2000 but this would be a bit overkill and I expect it to be too expensive.
It is still heavy metal shopping time in Europe and if one wants some fairly modern western stuff for not that much money its the time to buy it.