I'd have my doubts about any police in the West wanting a 105mm FH
For military, I'd say for MOUT something with turretted FH would be better and then why go for 105mm FH when you can have 120mm NEMO gun-mortar. as for chassis, why not? Throw in some add on armor that will give you say 23mm AP and RPG resistance and you have a handy close support IFV with a big bang.