Purchasing Custom Iphone5 Case Via Paypal

I bought wholesale from a Chinese seller, and paid via Paypal as there are no better way.

I've at least a certain "low" feeling of security using Paypal but it's better than MoneyGram or WesternUnion or T/T.

Anyways, as another level of protection, I requested seller to invoice me.

He sent me a black invoice without discription but the price is correct.

He told me not to put anything on the Paypal, but as a level of protection, I decided to put "to pay for iPhone case x 100 by Mss. xxx"

He replied to me in an email as follows:

I said to you did't leave anything on paypal invoice

but you leave the "for iphone 5 100pcs via Fedex "

it's very danger for us ,the paypal maybe check our account

you know ,the paypal did't allow anyone sell the iphone case

this maybe go to court .and please don't do this next time ,OK?

I know what you need ,100pcs case iphone 5 , ship to thailand

via Fedex ,so please did't leave anything next time

thanks very much my friend

Which, I couldnt find anything to confirm that Paypal doesnt allow the sales of iPhone 5 cases (unless it's branded of course).

Can anyone help to confirm this? I'm becoming very suspicious of this seller.