If you want to compete in "CAPS" (Basically airsoft IPSC) a TM 4.3 or 5.1 will probably be what you're aiming for and you can make it look exactly like any racegun you want. Be warned though some of these raceguns can get pretty pricey once you start to dabble but you should know that being a real steel IPSC shooter.
As for the AEG it's your choice. Take a peruse (in the proper definition sense: to look closely and intently at) through the classifieds for guns that match your budget. Buy local as well since you can hold the gun in your hands and check it out.
If you want an MP5 that's great, lots of internal parts available for it and it's somewhat common so external parts and accessories shouldn't be that hard to find. I have no experience with MP5's and the brands.
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE