You may want to check with play Asia on which type of scart cable they sold you. If it is a Japanese scart, then you will most likely need a converter for a run of the mill scart to hdmi box. However, if it is a euro model, you may simply need to add some 220pf caps to the rgb lines inside the scart cable. It all really depends on your setup. In my searches, I mostly came across euro cables and it is what I use with my N64 and snes. Unfortunately, it seems that not all scart cables are made the same because one set of cables I purchased kept producing a low hum in my audio. I opened up the cable but couldn't find any noticeable difference between it and another cable that was quiet. It probably has something to do with the quality of the wire used.
You may want to look into a gbs8820 box for your upscaling needs. For the price (35-50) these work decently and connect directly to VGA. Personally, I have not been able to get mine to work correctly without going through a scart-to-yuv converter, which adds lag and which is why I sprung for a XRGB2+, but many others havent seemed to have any issues with them. There is a thread that goes into more detail regarding them.