Two guitars worth more than £6,500 were stolen from Musicstreet in Chequers Court, Huntingdon, on Friday, July 5, at about 3pm.
Cambridgeshire police have now released CCTV images of three men they would like to speak to in connection with the theft.
One of the guitars was a PRS Custom 22 in deep purple. The other was a Japanese Ibanez.
Anyone with information is asked to call police on 101 quoting 35/47676/19 or report online at www.cambs.police.uk/report.
Alternatively call Crimestoppers, anonymously, on 0800 555 111 or visit www.crimestoppers-uk.org.