It doesn't look all that rough to me, it just needs some elbow grease. I think you'd be amazed. Suntour arx doesn't get a lot of love, but I find it a very reliable group with great shifting. Great system for tightening the cables too! I've seen that tubeset a few times on japanese bikes. I think the PG stands for Plain Gauge. Looks to me that with some new bar tape and a new saddle you'd have a pretty cool bike.