Yes, these days you need to accept some data (even though you might not use it) with any 'bundle'. Several websites, including the MoneySavingExpert one, say that Lebara offers the cheapest bundles (with £3 a month usually being quoted). However they appear to be out of date, as Lebara's own website shows £5 a month as their cheapest monthly deal (although you can get that down to £4.50 a month if you pay annually).
If you OH only uses his phone for emergencies, then I suggest that he should go for the 1p Mobile Classic PAYG tariff, at 1p per minute or 1p per text. For more regular use though, I suggest that he should go with Asda Mobile (which, apart from anything else, has excellent customer service from UK call centres), paying a fiver per month for a 'bundle'. That's who I'm with and I'm perfectly happy with them.
https://mobile.asda.com/bundles/standard?bundle=BUN5