14" will be more readily available - i've a hankering for a set of these myself! Sometimes companies have 'special deals' - so shop around. Worth asking JLH - http://www.jlhmorrisminors.co.uk/store/ ... t&catId=20 - you have to phone Jono for a price - tell him I sent you! The 15" will no doubt fit - but not much clearance.
How about this huge selection . https://www.europaspares.com/WHEELS/ They are all sold as blanks so you can specify the PCD, number of studs and the size for them to drill for you. Quite pricy but well worth it .