I bought a ContiTech PP279-280LK1 Pro Series Plus Kit. It contains the tensioners, the balancer belt and the timing belt, the water pump and water pump seal and two seals for the cam shafts. It does NOT contain the power-steering, air-conditioning and alternator belts, while you have the thing apart its a good idea to replace them. It does not contain the small cam-belt tensioner spring, but unless yours is broken you can re-use the old one. I put it on my car and I have done 13,000 miles with the kit in with no problems at all. My car had 164,000 miles on it when I did the belt swap. I liked it so much I reviewed it for Amazon -

'I bought this for my Honda Legend, which is the UK version of the Acura RL. It was less than half the price of the cheapest one available in the UK, even with shipping from the USA. The belts are high-quality items which are guaranteed for 90,000 miles, which is remarkable. The belt changes in the UK are recommended at 105,000 miles, in the USA which has more variation in climate (hot and cold) the periods can be shorter, but 90,000 guaranteed miles is excellent. The water pump is extremely well made and is equivalent to the original equipment, and the tension adjuster idlers are the self same as those fitted to my car. There are also a pair of cam seals which are OEM, but which I did not use. The belt and water-pump replacement is a long job, although apart from cracking the pulley bolt and removing the cam pully, there isn't anything really difficult involved, though of course you have to make sure all your timing marks line up. I would recommend that you pay to download the original shop manual for the Acura RL as it spells out all the steps clearly and has diagrams and the torque settings. I would also recommend you renew the power-steering, air-conditioning and alternator belts while you are in there, this will require separate purchase. Bleed the cooling system as per the instructions given by Eric the Car Guy on YouTube. Make sure you clean the mating surface on the engine side for the water pump really carefully, and as the 'O' ring is rubber DO NOT use any sealant, just a tiny smear of silicone grease if you must. I followed the instructions in the manual and those with the kit, it took me 20 hours to do it in a parking lot, but you should be able to do it in half that if you are experienced. The kit is excellent and the car started first time, not a stutter or hesitation, is running smooth and true and leak free, tested it on the highway all the way to the red line. Excellent quality, excellent value parts which arrived across the Atlantic in about a week of ordering. Very happy.'