Well these turned out nicely. These are in sprite order:
1 3
2 4

They can be flipped for four directions.

pgo_ui_arrow_r.smd
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 11 11 11 00 1F FF FF 00 1F FF FF 00 1F FF FF 00 1F FF FF 00 1F FF FF 00 1F FF FF 00 11 11 11 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 10 00 00 00 11 00 00 00 1F 10 00 00 1F F1 00 00 FF FF 10 00 FF FF F1 00 FF FF FF 10 FF FF FF 10 FF FF F1 00 FF FF 10 00 1F F1 00 00 1F 10 00 00 11 00 00 00 10 00 00 00 00 00 00 00

pgo_ui_arrow_u.smd
00 00 00 00 00 00 00 01 00 00 00 1F 00 00 01 FF 00 00 1F FF 00 01 FF FF 00 1F FF FF 01 11 1F FF 00 00 1F FF 00 00 1F FF 00 00 1F FF 00 00 1F FF 00 00 1F FF 00 00 11 11 00 00 00 00 00 00 00 00 00 00 00 00 10 00 00 00 F1 00 00 00 FF 10 00 00 FF F1 00 00 FF FF 10 00 FF FF F1 00 FF F1 11 10 FF F1 00 00 FF F1 00 00 FF F1 00 00 FF F1 00 00 FF F1 00 00 11 11 00 00 00 00 00 00 00 00 00 00

=^_^=