var priceSublist = 'price' + CURRENCY_ID;
record.selectLineItem(priceSublist, '1');
record.setCurrentLineItemMatrixValue(priceSublist, 'price', 1, sell_price);
record.commitLineItem(priceSublist);

var sublistId = "price" + CURRENCY_ID;
recordObj.selectLine({ sublistId: sublistId, line: 0 });
recordObj.setCurrentMatrixSublistValue({ sublistId: sublistId, fieldId: 'price', column: 0, value: sellPrice });
recordObj.commitLine({ sublistId: sublistId });