Since you have no access to trading, finding replacements would be advised since Haunter and Graveler are pretty bad stat wise. I would suggest Misdreavus for Gastly (Only other Ghost alternative) it has decent Special Attack, Special Defense, and Speed, HOWEVER, Haunter's greater Speed and Special Attack will allow it to hit first more often, making it a decent Special Sweeper. Haunter is not good defensively.
As for Geodude, you have few options as well. I would suggest Rhyhorn, since it has stellar Attack and Defense, albeit it has low special defense. This attack makes him a good Physical Tank, and slightly more usable than Graveler. I hope I was able to help, ask if you need anything more.