I can recommend four bike shops within a commute of Swindon  

https://www.bassettbikes.co.uk/ - Bassett Bikes - Based in Royal Wootton Bassett -  They offer used and new bikes and a good selection of cycling items - bike service and repair. Does not sell clothing.

https://cycologybikes.co.uk/chippenham - Cycology - Based in Chippenham - excellent selection of cycling goods and they sell cycling clothing too 

https://foldingbike.biz/ - C H White & Son - Based in Malmesbury - Brompton and Tern Dealership - Folding bike specialist. Service and Repair.

http://www.marlboroughbike.co.uk/ - The Marlborough Bike Company - Based in Marlborough - An independent bike shop serving the cycling community. Bike service and repair. Also clothing, lights, shoes, pumps, helmets, parts and tools.