I have a 1975 VW Westy Camper, will my 195/70 R14 tires carry the weight which is about 3000 lbs I am told.
The weight which most tires will support is called the Load Rating and on certain tires it is stamped on the tire sidewall as a code letter, but virtually all tires have important information stamped in small letters close to the bead (the area which touches the wheel). There you will see the maximum load in both kg and pounds which that tire is designed to carry together with the maximum air pressure which you should use.
The more weight you carry, the more air pressure you need, so if you are carrying the maximum weight then you will likely need to be close to the maximum air pressure.
When you find this information on your tire sidewall, remember that the maximum weight is per tire. Since your vehicle has 4 tires, you might simply divide the weight of the vehicle (3000 pounds) by 4 to get a load of 750 pounds per tire. If either the front or back, for some reason, is considerably lighter or heavier then you might have to make some adjustment for this. This is why you might have noticed on the tire information placard
of some vehicles that the front and rear tires have different air pressure requirements.
In any case, most passenger tires usually are capable of carrying more than 750 pounds, so if your information is correct, you should have no problem with the tires you plan to use.