For AMR/MR maybe Mirko Oremuš, if you're patient and wait a few years his stats will increase with the right training, in my Hajduk save I had played him in my first team for 7-8 seasons and always performed about 7.5 ratings even in the Champions League...
For CB you have loads of youngsters, maybe Galeano would be a good choice or if you're lucky an awesome regen...
For STC you have Jelavić... dunno who you can buy though...