Looking at the draft value chart, here's more trade combinations than you need (or want):
#78+#90 (both 3rds) = #56 (SEA)
No single 4th will get us into the 2nd, we'd have to package at least 2 of them:
78+134+143= 63/64 (KC/TB)
78+125+143=62/63 (GB/TB)
78+125+134= 61/62 (BUF/GB)
78+119+143=61/62
78+119+134=60/61 (NO/BUF)
78+119+125=59/60 (CLE/NO)
Now just to get silly...
90+119+125+134+143=58/59 (KC/CLE)
90+119+125+143=63 (KC)
90+119+134+143=64 (TB)
90+119+125+134=62 (GB)
Bored yet? :p