Indoor Rectangular Window Pots

I am trying to find some attractive indoor window pots approx 8" x 8" x 24" or 36" wide.

Something that has a glazed finish ie (fired clay), with a pale green / brown or cream colour. (A water tray would also be necessary.)

Like this but 2 or 3 feet wide;



I've looked around several garden centers / DIY stores and can only find plastic or terracotta, rectangular pots.

Could anybody recommend a supplier / retailer I could buy some pots from please?

Also, the terracotta pots I currently use have a white limey residue on the outside, is there a way to prevent this?

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EDIT: After looking around 5 DIY chain stores and about 8 garden centers in the past month, I have found some suitable pots in Blooms Garden Center (Rugby) in about 10 different styles / colours. :thumb: Although it's cost me £40 in petrol finding these, plus all the impulse buys at various garden centers. :(

As for the limey terracotta problem I mentioned, somebody has pointed me towards a waterproof acrylic spray.

Link: http://www.decoratingdirect.co.uk/viewprod/k/KEECCV/

Perhaps best not to use it on any pots used for kitchen herbs though.