It all depends on your goals. GH at an HRT dose may benefit you more than it would a younger person, since you are a little older. The older we get, the less we produce. An HRT dose would be just 2iu a day. I'd take it first thing in the AM. This would help with fat loss, overal health and long term, lead to better muscle gains. Keep in mind that this is a long term thing. I'd stay on for as long as you can. Ideally, you'd just stay on for as long as you want to train and grow. At the least, I would stay on for 4-5 months, during a dieting phase. If you use more, 3-4iu, it will lead to better fat loss. Then reaching into the 5 plus IU range, you'll start to see more muscle growth, along with test. 

There are a lot of options for GH, but I would suggest you use the best quality you can afford. Hyge is a good brand and Naps get them directly from the manufacturer. The generic color tops will work too if you are on a budget. I prefer Hyge when I can. They have always been consistently good