Stamp question

Hi all! May seem silly, but I can't seem to find the answer on the internet so I thought I would turn to you helpful strangers.

I bought these wedding stamps today and I'm not sure which way to display them on the invitations. Can I place them on horizontal as pictured? Or do they need to be displayed vertical with the text facing up?

Just wanted to ask before I put them on all my invites. Thanks!

https://store.usps.com/store/browse/uspsProductDetailMultiSkuDropDown.jsp?categoryNav=false&navAction=push&navCount=0&atg.multisite.remap=false&categoryId=wedding-stamps&productId=S_563004