curl --request GET \
  --url https://api.rivermarkets.com/v1/orders/{order_id} \
  --header 'x-api-key: <api-key>'

{
  "river_order_id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "order_type": "<string>",
  "time_in_force": "<string>",
  "qty": 123,
  "buy_flag": true,
  "status": "<string>",
  "subaccount_id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "created_at": "2023-11-07T05:31:56Z",
  "updated_at": "2023-11-07T05:31:56Z",
  "complex_order_ids": {},
  "price": 123,
  "river_id": 123,
  "custom_asset_id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "expiry_ts_utc": "2023-11-07T05:31:56Z",
  "traded_qty": 0,
  "average_price": 123,
  "fees_paid": 0,
  "reject_reason": "<string>",
  "fills": []
}