Several years ago there were a number of us in f&c who built a very similar plastic fantastic tlr kit ....... I forget it’s name but it was a laugh.
I honestly cannot recall what film I used..... I wouldn’t fuss over anything special unless you like ´Diana camera type results from plastic lenses.
Based on uk light, especially at this time of year I would go with a 400 speed.
I went monochrome but iirc a few other folk played with colour.
Mine fell to bits ( I lost a section of lens) part way through its second film !