Can one buy new clothes when in year of mourning? What about sales? Is it the same halachos as in nine days?
There isn’t an issue with buying the clothes, but with wearing them. He may buy the clothes in order to wear them after the 12 months is over.
Undergarments and socks that are used to absorb sweat are permitted to wear even if they are new.
If there is a sale he may buy the clothes, and wear them after 12 months.
During the nine days we don’t but new clothing, and according to some poskim it is permitted if there is a specific need, such as if it will be more expensive later, or for a newborn that doesn’t have clothes, however during 12 months we may buy them even without a need. They just can’t be worn.
Badei Hashulchan 389-59, R’ S. Z. Auerback zt”l in Ohel Chana ( in the back of Pnei Baruch) question 2. Niotei Gavriel HIlchos Bein Hamitzrim 31-2.