TV and Radio Aerial for 7.5Tonne box

Hi, 

wee are looking for a good aerial for our TV and also our Radio.  We are in a 7.5tonne Daf horsebox.   Our radio is an old style radio and we want the fittings to be the same and not have to rewire etc.   We have a radio at present but it is not really very good.   We would also like to have a good TV reception, for me when I am cooking inside !!  It cannnot be mounted on the roof as the roof is not strong enough, also it cannot be too big as we need to fit through small roads etc as we are touring Scotland.  Any advice please many thanks.