Physiological leaf roll (as imafan said) is more likely a response to heat not cold. And 55 degrees is not that cold
What size was the seedling when you got it? It is barely over the top of the pot now. If it was much smaller, it would have been sunk down in there and shaded by the pot sides. Unless you are planting trees, soil should fill the pot. What is the soil like? Hard to tell from pictures, but it looks pretty dense and compacted. And it is a very large pot for such a small plant. Tomato plants need large pots, but usually they get up-potted to that - start in 3 inch pots and move to bigger ones as they need it. The trouble with a large pot like that, is that it is way more water than the plant can use, so the soil tends to stay wet, especially if the soil is heavy and moisture holding anyway. I was also wondering how big the seedling was when you got it, because your plant now looks pretty small for two months (besides all the other problems). If you planted the seed two months ago, and all was going well, I would expect a bigger plant.
I haven't grown Mr. Stripey, but it may have been a difficult tomato variety to start with anyway. I seemed to remember a lot of complaints about it, so I used the search box to find what people have said here about it:
I once had a box-store bought "Mr. Stripey" that grew into a lovely healthy plant that produced one (1) freakin' tomato[ the whole season].....
https://www.helpfulgardener.com/forum/vi ... ey#p305379
For some people in some years, Mr. Stripey has produced a "bull" plant which is all foliage and no flowers.
https://www.helpfulgardener.com/forum/vi ... ey#p329070
I have yet to find anybody who has had success growing Mister Stripey.
https://www.helpfulgardener.com/forum/vi ... ey#p330181
elsewhere on the web, I found this:
I'm worried because I've been reading online about how some people say this particular variety is bad; it tastes bad, doesn't produce, etc. …There are many who think well of Mr Stripey and many who would never suggest that someone grow it. And I'm in the latter group and put Mr. Stripey way down on the possible gold/red bicolor varieties to grow. ..The most common complaints are that it's a spindly plant and poor fruit production and that there are other bicolor varieties that are better…..Hi Noteybook, I'm with Carolyn. Grew them last year, not impressed at all. Would never grow them again….If I could only grow 3-10 plants I wouldn't consider this cultivar. They drop blooms and are very late.
I'm sure now I will get some Stripey lovers writing in to say how much they love them. Like I said, I don't have personal experience, but it seems like there's a lot of complaints out there about them.
Anyway yours is probably diseased, certainly failing to thrive, and this late in the season not worth continuing to fuss with. It is a late producing variety, 80 days to maturity. And days to maturity is usually counted from when a transplant the size of yours now is planted in the ground. If it were healthy and doing well, you would barely have time to get one tomato before frost kills it, if you are in some cold winter area.