I have bought a $40 raft (Intex) from Clark Rubber and reinforced it with 3 layers of poly tarp which can be attached to each other and to the vinyl tarp with polyethylene tape (from greenhouse suppliers). Gaffer tape might work too. You could also use tarp clips if you prefer. This makes it well-nigh indestructible. The tarps come in three weights: 100grams/square metre, 150 and 200 equating roughly to 4,5 & 7 oz per square yard). It is possible to make a double paddle up with the oars they supply by cutting a thread on the end of the plastic handle with a metal pipe fitting. The paddle is VERY delicate. The advantage of such rafts is that they are very cheap and can be stowed in your favourite hunting spot approx two per 25 litre canoe drum. Then when the need arises to transport some venison out or if you twist your ankle or are just in a hurry to return to your beloved they come in very handy and are not so expensive if they are lost to a flood or wildfire. You can saw the rowlocks off if they get in your way. I use my inflatable sleeping mat in the bottom for extra padding, flotation and insulation from cold water. I think they make a very good introduction to packrafting.
I do not intend that they should be seen as competition to Alpackas but they might well lead someone on to buying such a more robust raft after they have thoroughly trashed their ‘cheapie’. I own an unrigged Fiord Explorer which I explicitely bought for that eponymous purpose. I hiked three days in Fiordland New Zealand to just below Loch Marie on the Seaforth River and rafted down the river to the Dusky Sound (or Fiord) in 2009. Not a bad effort for a 60 year old. There were a really lot of people sized sharks in the Fiord so that part of the trip was rather exciting, but the hut at Supper Cove at the end of the trip is maybe the most beautiful place on earth. You can find lots of snaps on Google Earth. There are also at least two rapids which MUST be watched for and portaged. I believe I may have been the first person to solo canoe the Seaforth River but I understand a deer culler with a broken leg was rafted down the river on a tractor inner tube during the 1960’s. I came in from Lake Hauroko. If you came in from Manapouri you could raft down from the Kintail Hut to Loch Marie. I know there are a couple of rapids and a Lake in this stretch but I have not (yet) paddled it. You can paddle across the Loch being very careful to avoid the innumerable submerged branches but you MUST portage out of the Loch. There is an immense cascade at the exit. Put back in below the Bishop Burn.
An ‘Aerovest’ makes a very cheap, light life jacket though it is not recommended or legal for this purpose. It is certainly a lot better than NO life jacket. It also keeps you warm. You need both the straws it comes with. One to inflate it and one to deflate it to just the right ‘fit’. You could use another piece of tape to attach it more securely. I figure it WOULD save your life.