Welcome to the club.
Your AC, how do you know it needs a charge?
If it is not cooling the coil up on the roof may need to be cleaned. Do you have a manual on the AC unit?
If it is actually a gas problem, this is not normally a do it your self thing. Being an 86 unit, it very well could be using the older refrigerant. Each state may have different laws on the use of the older style Freon. Some may only be available from reclaimed units that a repair facility only has access to. I have never charged one of these units only been involved on heat pumps and industrial cold storage units but the concepts are similar.
Good luck and happy camping
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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