I have developed malar bags. What treatment would you recommend?

There is no perfect solution for festoons, so you are going to get a lot of different opinions about how to treat them.  Unfortunately they may not all work!!  Sometimes if there is a lot of excess skin a blepharoplasty with some laser resurfacing will work.  Dermapen may help, but not the best option.  Venus is a type of radiofrequency.  This may help them but no guarantee.  Not sure what your doctor wants to do for 5K.  You just have to have realistic expectations. 

Malar bags or festoons are very difficult to treat.  Surgical removal requires an extended lateral lower eyelid incision which is very visible through which a modified cheek lift can be done.In my opinion the best treatment for malar bags is dermal filler injections into the depression below the bag to camouflage the malar bags.

Malar bags can be caused by 2 different things. First, it can be caused by allergies which cause swelling in the under eye area. If this is the case, you need to treat the underlying problem. The second problem that causes them is aging and descent and deflation of the under eye area. Depending on the particular problem, there are two options. The first is a lower blepharoplasty (eyelid lift) and cheek lift. This is the most definitive method. The other is injection of the area over the orbital rim to elevate the malar tissues and fill the depression under the eye. The injection may have to extend down to the mid malar area in order to elevate tissues enough to eliminate the "bag." Unfortunately, the price quoted is not unreasonable for either option. Neither of the two options you mentioned will correct the problem.