I would be surprised if you can get cover from the UK (other than through a Cypriot agent), but it is worth investigating.
Pacific Insurance Brokers in Paphos usually reply to e-mails (and most companies here still use fax extensively).
If you are worried about the cost of the phone calls whilst ringing around Cyprus from the UK, use Skype to make the calls for a few coppers. Though frankly a few pounds spent on the phone will be the least of your expenses if you are thinking of letting out the property..
Try Pacific on
[email protected] Phone +357 (26) 911193
Fax +357 (26) 911196
though I am a tad annoyed with them at the moment for underquoting for my toy car by €150, because they hadn't allowed for the fact that a cabrio is classed as a convertible, which commands a higher premium