Pretty sure the 9000 is as big as they go- basically a rebadged 2188 and as such, you will find problems when it comes to wrap handle mounts and chainbrake flags if you want to put Husqvarna stuff on an Ex Jonsered body. However, if you use the Husqvarna 390 tank, the Husqvarna wrap handle will fit, but the chainbrake flag most likely wont. There is a slight difference between the Jonsered and Husqvarnas in that region and although they look close- they do not interchange.
So to answer the above, stop at the 390XP, no bigger CC Redmaxes (to the best of my knowledge) and stop at the 3 series family of Husqvarnas- there is no 5 series Jonsered equivalent, so therefore no Redmax equivalent.