Limited diet... causing issues

hi just wondering for those of you with children who have restricted diets, how you manage when outwith.

my son is 8 and his restrictive diet is manageable when in the house and places where we can take a packed lunch.

we were away a few days and things were manageable up until the last day . We had visited Blackpool on the way back which was a planned stop but we had not thought about the food.  We were luck enough to find a Greggs so L was happy with a couple off sausage rolls, cue breathing for me as it took us a while.  With a lot of stress and worry as we couldn’t find anything reaasonable for him up until that point. We very rarely go out to eat for this reason. The eating issue Aswell as realising that certain restaurants gave L sensory overload, music lights etc and anxiety if not having anything he would eat were just not fun so normally avoided. 

My question is has anyone else’s child extended there diet eventually or is this the future for L, his weight suffers due to the high carb intake and I feel I have to be quite restrictive of the things he does eat.

these are:

toast and marmite, potato scone with marmite, wrap with cheese and marmite, micro chips, beans and Richmond sausages, garlic bread, coco pops, strawberries, melon, spaghetti and carbonara (Aldi’s) on the odd occasion, crisps set types and organic fruit bars on occasion.   I realise this list appears extensive too some but there’s not much you can play with for meal ideas. He won’t eat regular chips etc and most foods are certain makes so that doesn’t help either funny enough he even has certain sweets he will eats according to colour etc although I try and restrict these too.

We have tried Various things when he was younger ie food reward charts, putting one new thing on plate, putting down the meal and if he ate great if not then he had to wait.  These did not work and were very stressful, it appears it’s due to sensory issues taste, touché, smell etc. Yellow food. 

It would be great if I heard someone else’s experience of this

thank you in advance.

tracky