Assuming we're dealing with an Automatics weapon of some kind:
- Foregrip (1 mod slot): 1 RC
Auto-adjusting weight (4 mod slots) 1 RC on first burst, 2 total on the second, 2 on FA mode - Shock pad or stock (no slot): 1 RC
- Gas Vent 3 (2 mod slots or Barrel mount): 3 RC
- Personalized Grip (1 mod slot): 1 RC
Electronic firing (2 mod slots): 1 RC - Heavy Barrel (3 mod slots): 1 RC on Full Bursts
So if you go with auto-adjusting weight, stock/shock pad, Gas Vent 3 accessory, and Personalized Grip or Electronic Firing, you've got 7 RC as long as you fire 2 bursts or a big one, with 5 or 6 mod slots and the barrel mount used. The Ares Alpha assault rifle and FN P93 Praetor SMG, however, come with 2 respectively 1 recoil compensation from special chambering mechanisms, so the Ares Alpha can get up to RC9, and the Praetor up to RC8, without using a bipod or tripod. However, both weapons are Forbidden.
There's also the Ingram SuperMach 100, which comes with 3 points of Recoil Compensation but lacks a Barrel mount, meaning a Gas Vent has to come as a modification: however, Foregrip + Folding Stock (included) + Gas Vent 3 means it too can get up to RC8, although it has a lower base damage.
And like SlowDeck states, there's also an optional rule about getting recoil compensation from high Strength somewhere in SR4A.