Have to open up an old cassette tape of yours that was sealed with glue to repair the splice?  And have the shell get destroyed.  Here is an economical replacement shell.  The only thing missing is your reels of tape.  These come with a new felt pad, the inner slide sheets (these are very important they keep the reels from rubbing against the shell) everything else needed to work with your reels of tape.  
 
The style of cassette shell pictured is what you will receive.  These are a clear/smokey gray color.  The slip sheets do have writing on them.  However this can be easily removed with some q-tips/cloth and 91% Isopropyl Alcohol.  Only takes about 2 minutes per sheet.  I have included pictures of what this shell looks like when all of the text has been removed from the slide sheets.  However this is not how they will arrive.  
 
These had small labels on them that I removed.  However there will be some adhesive residue left on these that will need to be cleaned off (you can see it in the upper left hand corner of the tape in the main pic).
 
Price is for one complete shell.   These shells are held together with Phillips head screws for easy access.  
 
Shipping Details:
 
USA Customers ONLY, Shipping is a flat fee of $4.80
Orders $40 and over get FREE shipping via USPS Ground Advantage.
 
Canadian Customers, Shipping is a flat rate of 10.99 for up to $100 worth of merchandise
 
International Customers,
Shipping to most countries is $13.99 for the first $100 worth of merchandise.  This is through Asendia/USPS. 
 
Also, depending on your country, you may be charged an excise tax, VAT, etc on your end.  I do not collect any of these taxes or fees.