This abaya is actually a hand-me-down. It was in-style here in Oman about 3 years ago now. I still wear it for work because I feel embroidered flowers in anything a-line with wide kimono sleeves is pretty standard still for casual wear. As stated, it is a-line with kimono sleeves which have an embroidered panel affixed and then a piece of courdinating dove-grey fabric at the sleeve. The abaya itself is saloona and the trim if poly-chiffon. The embroidered panels meant just for sewing onto abayas are sold in pretty much every tailoring goods supply store here so I believe this abaya was made at a tailor and not a brand. But the hand-beading and additional of real crystals [making the sleeve actually quite heavy] suggest that there was a possibility it was from a boutique and not just a higher quality tailor who can offer handwork.
To get one of these made without handwork is usually 35-40 OMR depending on how tall the sister is but can be made for less if a cheaper fabric (still decent but not the best quality) like black crystal is used instead. This abaya came with a matching shayla and you can see the bading and crystals [although it doesn't show the crystals nicely] below: