That error means that the signature is invalid. coinb.in has, for quite a while now, been known to have issues with their signer which results in invalid signatures.
Looking at the transaction, it is actually incomplete. It is completely missing the redeemScript.
I thought so. I have tried using Bitcoin Core to build the transaction.
First, I created the unsigned transaction using this command.
createrawtransaction '[{"txid":"516f88d66bb73ef1903e302dad374af5994fa030062b0438abee79189820d2bb", "vout":0}]' '{"3DgECca9xyBAvEcwrtF5QnS5HkEGxxa81y":0.00048}' 1530172800
Then I signed it with the private key using this:
signrawtransaction "0200000001bbd220981879eeab38042b0630a04f99f54a37ad2d303e90f13eb76bd6886f510000000000feffffff0180bb00000000000017a914837b578229e3e15172f819dc4a43ecdb46a87e30878095345b" '[{"txid":"516f88d66bb73ef1903e302dad374af5994fa030062b0438abee79189820d2bb","vout":0,"scriptPubKey":"a914395060fa01753cb19684415f6720d7bdb9b689e487","redeemScript":"046079345bb17541046d37106834e29cc16fb64a6fed20a5ce9b7b4be9d64f2da69c2bedb3d9b103bda4be4a9fde5b3af85d61db74976c4cf01610e84279300f5f2071a8eb05ea808bac", "amount": 0.00048}]' [...]
And received the following error: Unable to sign input, invalid stack size (possibly missing key)