Convert SQL Script With JOIN's to SSIS

I've been tasked with converting several existing SQL scripts into SSIS packages. While some of the scripts are fairly straightforward, some of the scripts contain multiple JOIN's across multiple tables. While I have always just used a simple Execute SQL Task or an OLE DB source with a script, I've been asked to do away with any references to any other tables/databases in the source. Here is an example of one of the scripts:

INSERT INTO [dbo].[DimEngagementVehicle]
           ([EngagementVehicleSourceKey]
           ,[EngagementVehicleCode]
           ,[EngagementVehicleDesc]
           ,[EngagementVehicleCategorySourceKey]
           ,[EngagementVehicleCategoryCode]
           ,[EngagementVehicleCategoryDesc]
           ,[EngagementVehicleTypeSourceKey]
           ,[EngagementVehicleTypeCode]
           ,[EngagementVehicleTypeDesc]
           ,[GlobalEngagementVehicleKey]
           ,[GlobalEngagementVehicleDesc]
		   ,[GlobalEngagementVehicleTypeKey]
           ,[GlobalEngagementVehicleTypeDesc]
           ,[RowIsCurrent]
           ,[RowStartDate]
           ,[RowEndDate]
           ,[RowChangeReason]
           ,[InsertAuditKey]
           ,[UpdateAuditKey]
           )
 SELECT		 hs.health_screening_key
			,hs.source_key
			,hs.health_screening_desc
			,s.source_key
			,s.source_code
			,s.source_desc
			,v.rbh_vendor_key
			,v.rbh_vendor_code
			,v.rbh_vendor_name
			,3  AS [GlobalEngagementVehicleKey] -- 'Health Screening '
			,'Health Screening ' AS [GlobalEngagementVehicleDesc] -- 'Health Screening '
			,2 AS [GlobalEngagementVehicleTypeKey] -- 'Active Engagement'
			,'Active Engagement' AS [GlobalEngagementVehicleTypeDesc]
			,'Y' AS [row_is_current]
			,getdate() AS [row_start_date]
			,'12/31/9999' AS [row_end_date]
			,'N/A' AS [row_change_reason]
			,-1 AS [insert_audit_key]
			,-1 AS [insert_audit_key]
FROM [RBH_DW_STAGE].[dbo].health_screening hs
INNER JOIN [RBH_DW_STAGE].[dbo].[source] s on hs.source_key = s.source_key
LEFT JOIN [RBH_DW_STAGE].[dbo].[rbh_vendor] v ON v.rbh_vendor_code = hs.vendor_screening_id
WHERE NOT EXISTS
(SELECT 1 FROM [DimEngagementVehicle]
	WHERE [GlobalEngagementVehicleTypeKey] = 2
	AND [GlobalEngagementVehicleKey] = 3
	AND [EngagementVehicleSourceKey] = hs.health_screening_key)
GO

I know that either LOOKUP or MERGE JOIN could be used here, but not quite sure how to implement it in a package.

Any insight or assistance would be greatly appreciated!

Thanks!

A. M. Robinson