Hello Stewart,
Nothing in my junk box but Farnell have 3.579545 MHz in HC49U holders.
http://uk.farnell.com/webapp/wcs/stores/servlet/Search?catalogId=15001&langId=44&storeId=10151&categoryName=All%20Categories&selectedCategoryId=&gs=true&st=crystal%203.579545%20mhz
only 50pence (but large delivery charge!) 73 Malcolm GM3TAL